Best prices around for >2 layer boards. 4-layer boards up to 30 sq in. with 7/7 are $210 for 5, including shipping. Turn time is about 10 days including DHL from China. Service is not as fast as bigger outfits like Advanced Circuits, but still fine.

Offers their own free (proprietary) schematic and PCB layout software -- easy to use, but you are locked into using their service. Integration with ordering system simplifies the process of ordering boards.

Similar to PCB123, in that they have free propietary schematic and layout software, but their Mini-Board service (3 identical boards, 2.5" X 3.8", no silkscreen) is priced well at $51 total, which includes shipping. If you need small boards quickly, this is a good choice, since they ship the next business day.